1. Field of the Invention
The present invention relates to an organic light emitting display and a method for fabricating the same to improve color purity and efficiency.
2. Discussion of the Related Art
The recent advent of information-dependent age has brought about rapid development in the display field that visually displays electrical information signals. In this regard, a variety of flat panel display shaving superior properties such as slimness, low weight and low power consumption have been developed.
Examples of flat panel displays include liquid crystal displays (LCDs), plasma display panels (PDPs), field emission displays (FEDs), organic light emitting displays (OLEDs) and the like.
In particular, an organic light emitting display spontaneously emits light, which has advantages of rapid response speed, superior luminous efficacy, excellent brightness and wide viewing angle, as compared to other flat panel displays. Such an organic light emitting display includes an anode and a cathode which face each other such that a light emitting layer is interposed therebetween. Holes injected from the anode recombine with electrons injected from the cathode in the light emitting layer to form electron-hole pairs, i.e., excitons. Light is emitted by energy generated upon transition of the excitons to a ground state.
In a general organic light emitting display, a configuration in which a blue light emitting layer is formed commonly in red, green and blue sub-pixels by deposition is suggested in order to simplify a fabrication process. However, when the blue light emitting layer is formed in the red and green sub-pixels, upon emission of red and green light from the red and green light emitting layer, blue spectrum is also emitted and color purity of red and green light is disadvantageously deteriorated.
In addition, when a blue light emitting layer formed by a general deposition process contacts a hole transport layer formed by a solution process, lifespan and efficiency of the blue light emitting layer are disadvantageously deteriorated due to surface non-uniformity between an interface of the hole transport layer and an interface of the blue light emitting layer.